Aston (US): Donald Trump has rolled out a plan aimed at making child care more affordable, guaranteeing new mothers six weeks of paid maternity leave and suggesting new incentives for employees to provide their workers childcare.

Spurred on by his daughter, Ivanka, Trump waded into topics more often discussed by Democrats. Trump unveiled the proposals in a speech in a politically critical Philadelphia suburb on Tuesday as he tries to build his appeal with more moderate, independent voters - especially women.

Republican presidential candidate Donald Trump. AP

Child care is one of the biggest expenses many American families face, surpassing the cost of college and even housing in many states.

"We need working mothers to be fairly compensated for their work, and to have access to affordable, quality child care for their kids," Trump said in Aston, Pennsylvania.

"These solutions must update laws passed more than half a century ago when most women were still not in the labor force."

The campaign says the payments would be provided through existing unemployment insurance - though it has yet to spell out how the system would cover those costs.

Trump's Democratic opponent, Hillary Clinton, has called for 12 weeks parental leave for both mothers and fathers paid for by taxes on the wealthy.

Trump previously proposed reducing child care costs by allowing parents to fully deduct the average cost of child care from their taxes. On Tuesday, he expanded that proposal to allow families with a stay-at-home parent to qualify for the deduction and to include costs associated with caring for elderly dependent relatives.

The deduction would apply only to individuals earning $250,000 or less, or $500,000 or less if filing jointly. But because Trump's proposal is a tax deduction rather than credit, its greatest benefits would go to affluent households.

More than 40 percent of US taxpayers don't make enough money to owe taxes to the federal government, meaning they would not benefit from a deduction. Lower-income earners would receive child-care spending rebates through expanding the existing Earned Income Tax Credit, the campaign said.

Trump also proposed incentives for employers to provide child-care options at work. But some of his proposals to prod businesses and communities into providing childcare and other services are anathema to conservative orthodoxy.

At one point, Trump was interrupted briefly by a crying baby - but, unlike at a rally in August, he did not suggest he wanted the child ejected.